One Time I Laughed Really, Really Hard

I don't often laugh enough to make milk come out of my nose but those few times i do i just cant stop laughing. I remember this time when i was hanging out with my friends and we saw someone who was riding on a skateboard just fall over. At first we didn't think much of it. It wasn't until we kept walking and saw the same guy fall over again. He also figured out we saw him fall twice and tried to play it off like nothing had happened. The funniest part was after the second time he started walking instead of riding his skateboard.